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SWAP (Soil-Water-Atmosphere-Plant) was evaluated for its capability to predict groundwater table behaviour under drained condition with a semi-arid monsoon climate in Haryana (India). The performance of the model was tested using data for water table, drainage discharge rate and cumulative discharge A close agreement was observed between the measured data and simulated value. SWAP simulated values ranged within absolute deviations of 0.17-0.18 m for water table, 0.87-1.07 mm day-1 for discharge rate and 7.8-39.4 mm for cumulative drain discharge rate when compared to observed values. The calibrated and validated model was used to predict excess water stress utilizing SEW30 index for different spacing under three rainfall situations. The results revealed that SEW30 exceeding 100 cm day-1 could be encountered with drains spaced at 75 m while it would remain within 50 cm day-1 with drains spaced at 50 m during normal and/ or above normal rainfall years. No excess water stress problems occurred with drains spaced at 25 m or in years with below normal rainfall in any of the test spacing. Long-term simulations revealed that residual effect of one year do not affect the water table during the next year under drained condition.